Rock drilling mechanism



. Mal'Ch Q OSGQOD ROCK DRILLING MECHANISM Filed Jan. 5. 1956 4 Sheets-sheet?.

March 15, 1938. c. F. osGooD ROCK DRILLING MECHANISM Filed Jan. 3. 1936 4 Sheets-Sheet 3 ai, u

C. F. OSGOOD ROCK DRILLING MECHANISM March 15, 193s;

Filed Jan. 3. 1956 4 Sheets-Sheet 4 15 and the rock drin.

Patented Mar. 15, 1938 UNITED STABS PATENT (lFFIClE'.l

ROCK DRELLENG MECHANISM Massachusetts Application .lanuary 3, 1936, Serial No. 57,394

20 Claims.

This invention relates to rock drilling mechanisms, and more particularly to improved feeding and guiding means for a hammer rock drill of the mounted type.

An object of this invention is to provide an improved rock drilling mechanism having improved feeding and guiding means whereby the rock drill is fed and guided in an improved manner. A further object is to provide an improved tubular guiding structure having a guiding surface for guiding a feeding element of the feeding means and a guideway along which the rock drill is guided during the feeding operation and improved connections between said feeding element Yet another object is to provide an improved rock drill guide structure embodying a tubular guide member having a guiding surface along which the reciprocable feeding element of the feeding means is guided and having improved guiding means for the rock drill and improved connections between said reciprocable feeding element and the rock drill. Yet another object is to provide an improved drill guide structure having a guiding surface within its rearward portion for guiding the reciprocable feeding element of the feeding means and having extending along its forward portion a guiding surface for the rock drill and a connection between the rearward portion of the reciprocable feeding element and the rear end of the rock drill. Another object is to provide an improved feeding andl guiding structure for a rock drill whereby, with an extremely compact mechanism, a relatively long feeding travel for the drill is attained. Other objects and advantages of the invention will, however, hereinafter more fully appear.

In the accompanying drawings there are shown for purposes of illustration several forms which the invention may assume in practice.

Fig. l'is a side elevational view of one illustrative embodiment of the improved rock drilling mechanism.

Fig. 2 is a plan View of the rock drilling mechanism shown in Fig. 1.A

Fig. 3 is an enlarged horizontal sectional view taken substantially von line 3--3 of Fig. 1, showing the feeding means in its fully lextended positio-n.

Fig. 4 is a View in longitudinal sectionv taken substantially on line 4-4 of Fig. 3, showing the feeding means in its collapsed position.

Fig. 5 is ,an enlarged cross sectional view taken V substantially on line 5-5 ofFig. 2.

Fig. 6 is a detail sectional view taken substantially on line 6 6 of Fig. 5.

Fig. '7 is a detail sectional view taken substantially on line 'l-l of Fig. 5.

Fig. 8 is an enlarged cross sectional view taken 5 substantially on line 8 8 of Fig. 2.

Fig. 9 is an enlarged cross sectional view taken substantially on line 9-9 of Fig. 2.

Fig. 10 is a view similar to Fig. 1 showing a modified form of the invention. l0

Fig. l1 is an enlarged View in longitudinal section illustrating the improved feeding and guiding structure shown in Fig. 10, the rock drill being omitted to facilitate illustration.

Fig. 12 is a cross sectional view taken substan- 15 tially on line I2|2 of Fig. 10.

Fig. 13 is a cross sectional view taken substantially on line Iii-I3 of Fig. l0.

Fig. 14 is a cross sectional view taken substantially on line |4--I4 of Fig. 11. 20

Fig. 15 is a view similar to Figs. 1 and 10 showing a further modified form of the invention.

Fig. 16 is an enlarged view in longitudinal section illustrating the improved feeding and guiding structure shown in Fig. 15. 25

Fig. 17 is a View in longitudinal sectiontaken in the plane of Fig. 16 showing the feeding means in partially extended position.

Fig. 18 is a cross sectional view taken substantially on line l-I of Fig. 16. 30

Fig. 19 is a cross sectional View taken substantially on line I9-I9 of Fig. 16.

In the illustrative embodiment of the invention shown in Figs. 1 to 9, inclusive, the rock drill is generally designated l and the improved feeding 35 and guiding means is generally designated 2. The drill guiding means comprises a pair of tubular guiding members 3, 3 of cylindrical form arranged in parallel side by side relation and rigidly fixed together at their ends by transverse con- 40 necting portions 4, 4. Secured to the lower portions of the tubular guides 3, 3 intermediate their ends is a transverse frame 5 having an integral swivel plate or trunnion 5 adapted to be clamped in the saddle mounting of a conventional drill support. 'Ihe rock drill l is of a conventional design comprising a hammer lmotor having a motor cylinder l provided with a rear head block 8, a front head 9 and a front chuck housing l0, the latter supporting, in a usual manner, a chuck for receiving the shank of a rock drill steel lil. As the particular construction of the rock drill does not, per se, enter into this invention, an illustration and description thereof is not considered necessary. The forward ends of the parallel 55 tubular guide members.

tubular guides 3, 3 are closed by heads I2, I2 suitably threaded therein, and these heads have cylindrical forward projections on which are pivotally mounted a pair of guide members I3 adapted when in closed position to embrace the drill steel i I to guide the latter during the the drilling operation. The rock drill I in this embodiment of the invention is supported directly on and between the parallel tubular guide members 3, 3 by the provision of a depending portion I5 which may be of suitable longitudinal length so as to provide sufcient bearing surface, and projecting between the guide members, while a cooperating clamping and guiding element I6 is removably secured to and spaced from the portion I5 as by screw bolts il. The elements I5 and I6 present arcuate bearing surfaces i8 and I8 slidably engaging the inner adjacent sides of the outer peripheries of the It will thus be seen that the rock drill is entirely supported by and slidable directly on the parallel guide members directly on the exterior peripheries of the latter without the intermediation of any 'other guiding elements, thereby greatly simplifying the 'guiding structure of the drill. Formed within the forward portions vof the tubular guide members 3, 3 are parallel feed cylinders 25, 20, stationary with respect to the guide members, and each containing a reciprooable feed piston 2 i. The piston rods 22 of the feed pistons 2| extend rearwardly through the rear packed heads 23 of the feed cylinders 2G and through the packed front heads 24 ofV parallel feed cylinders 25, 25 alined with the cylinders 20 and y reciprocably mounted in the parallel guide bores 26 of the tubular guide members. Fixed to the rear ends of the piston rods 22 and contained in the cylinders 25 are feed pistons 21. The rear ends of the parallel feed cylinders 25, 25 are rigidly connected together by a transverse connecting-'frame 28 extendinglbetween the cylinders, when the latter are in a forward position, through longitudinal slots 29 formed along the inner adjacent sides of the outer peripheries of the tubularlgude members, the slots permitting movement of the transverse connecting frame 23 withrrespect tc the tubular guide members during reciprocation of the 'feed cylinders 25. The rear head ii of the rock drill l is formed with a depending boss or lug 3l] having a conical bore 3l in which is secured, as by a nut 32, a conical front end portion 33 Vof a connecting rod 3e, the nut 32 being threaded at '35 on this connectingV rod. This connecting rod extends rearwardly longitudinally between Ythe guide members 3, 3 and is threadedly connected at its rear end at 35 within the transverse frame 28 and is held therein by lock nuts 31 threaded lon the connecting rod. It will thus be seen that as the feed cylinders 25, 25 are reciprocated within the guide bores 25 of the parallel guide members, the rock drill I is slid along its guiding surfaces on the exterior peripheries of the guide members.

Now referring to the means for supplying pressure fluid tothe feeding cylinders and the rock drill, it will be noted that arranged in a transverse bore 0 formed in` the rear head block 8 Vof the rock drill l is a rotary control valve 4I having an internal pressure chamber 52 to which pres-V sure fluid is supplied through a rpipe connection 43 from any suitable source of'supply. Arranged in a bore it parallel with the valve bore 4I is a rotary feed control valve d5, while mounted within the control valve 4I is ajvalve means 46 for regulating the feeding pressure. The rotary valves'i'and 45 and the'valve means 4B are generally similar to those described in Patent No. 2,015,678, granted October 1, 1935, to M. C. Huffman and as the specific structures of these valve means are clearly described in that patent, a description thereof herein is considered unnecessary, other than to state that the feeding pressure reducing valve 45 may be adjusted to regulate the feeding pressure and the feed control valve 45 may be operated to control the flo'w of feeding pressure to the feeding cylinders to effect reversal in the direction of feed irrespective of the feeding position'of the control valve 4l. The control valve 4I may be operated to control the supply of pressure fluid to the hammer motor of the rock drill and to the feeding cylinders. Pressure fluid is adapted to flow from the pressure chamber 42 in the control valve 4I through an Yaxial passage l (see Fig. 5) under the control of the feeding pressure reducing valve 46 to a passage 48 in the valve 4I communicating with a circumferential lgroove 49 (see Fig. 6), the latter in turn communicating with va forward feed supply passage 5D. A reverser feed supply passage 5I is communicable through a-circumferential groove 152 on the valve 4I (see Fig. 7) in turn communieating through a passage 53 vin -the valve II with the pressure chamber 42. The forward feed passage '50 is communicable through passages in the control valve 45 with an annular groove 54 on the forward portion ofthe connecting rod 34 in turn `communicating through a passage 55'in the connecting rod with a groove 56 in the connecting frame 28 and surrounding the rearward portion of the connecting rod. The groove 5'6 is connected by passages 51, 51 formed in the walls of the reciprocable feed cylinders 25, 25, with the forward ends of the bores of the reciprocable feed cylinders at the forward 'sides of the feed pistons 21. The reverse feed passage 5I is communicable through passages in the control valve t5 with an annular groove 58 on the Vforward portion of the connecting rod, in turn communicating'through a passage 59 Vin theconnecting rod with a recess 60 in the connecting frame at the rear Vend ofthe connecting rod, this recess vconnected by transverse passages EI, 6I in the connecting frame 28 with the rear ends ofthe bores of the reciprocable feed cylinders V25, 25 at the rear sides of the feed pistons 2?. The control valve '4I has a circumferential groove 62 (see Fig. 6) for connecting through a passage 55a the passage 55, with an exhaust passage 63, while the reverse feed passage 5I is'communicable through acircumferential groove 621 (see Fig. 7) on the control valve 4 I, when the valveis turned into its position opposite from that shown in Fig. '7, with an exhaust passage 65. Passages 66 extending longitudinally through the piston rods 22 (Fig. 3) connect the forward ends of the bores of the stationary feed cylinders 2U with the rear ends of the bores of the recip-rocable feed cylinders 25, while parallel passages S1 in the piston rods connect the rear ends of the bores of the stationary feed cylinders 20 with the forward ends of the bores of the reciprocable feed cylinders 25. The opposite side walls of the guide members 3, 3 are out away at 68 to permit access to the adjusting plugs 69 for the packings of therear heads 23 of the stationary feed cylinders 2B, 2U, it'beingpossible to insert a wrench through the opening 58 to effect adjustment of the adjusting plug 69. The adjusting plugs 'I0 for the packings of the front heads 24 of the reciprocable feed cylinders 25, 25 may be adjusted by insertion of a wrench throughthe longitudinal slots29, 29 cut-in the side Walls of the guide members. The throttle valve, as described in the above mentioned patent, has a pas'- sage forsupplying pressure fluid from the pressure chamber 42 in the valve to the supply passage of the hammer motor of the rock drill, as is usual in rock drills of the type disclosed.

The mode of operation of the rock drilling mechanism above described will be clearly apparent from the description given. When the valves are in the position shown in Figs. 6 and 7, pressure fluid may flow from the pressure chamber 42 in the throttle valve 4i, axial passage 4l past the feeding pressure regulating valve 46 and through passage 48, groove 49, forward feed passage 50, valve 45, passage 55a, groove 54, passage 55 in the connecting rod, groove 56 and passages 51 to the forward ends of the bores of the reciprocable feed cylinders 25, 25, the pressure fluid flowing from the bores of the cylinders 25 through the passages 61 in the piston rods 22 to the rear ends of the bores of the stationary feed cylinders 25, 2S. At the same time the opposite ends of the bores of the cylinders 26 and 25 are connected to exhaust through the passages 56 in the piston rods, passages 6l, 6l, recess 60, passage 59 in the connecting rod, groove 58, valve 45, passage 5i, groove 64 and exhaust passage 55. The pressure fluid in the bores of the reciprocable cylinders acts on the pressure surfaces of the .cylinder heads 24 to move the cylinders 25 forwardly within the guiding bores 26 in the tubular guide niembers, while the pressure fluid flowing to the bores of the cylinders 20 act on the rear pressure areas of the pistons 2i to move the latter forwardly within their cylinder bores, moving therewith the cylinders 25, upon completion of the forward movement of the latter with respect to the feed pistons 21, and as a result, the rock drill I is fed forwardly along the guiding surfaces of the tubular guide members. During relatively free feeding movement, the cylinders 25, 25 may more rapidly move relative to their respective pistons than do the pistons 2l relative to the cylinders 20, due to the effect of the long passages in the piston rods, but it will be understood that simultaneous movements between each piston and its respective cylinder probably occur during much of the feeding operation. When it is desired to effect revers-e feed of the rock drillv along its guideways relative to the parallel guide members, the throttle valve 4i is turned into the position opposite from that shown in Figs. 6 and 7, so that the groove 52 connects the reverse feed passage 5! with the passage 53 communicating with the pressure chamber 42 in the control valve 4i and the passage 5l)EL is connected by the groove Vt2 with the exhaust passage 63. .When the throttle valve is in this position, pressure fluid .may flow from the pressure chamber 42 through passage 53, groove 52, reverse feed passage 5i, groove 58, valve 45, passage 59 in the connecting rod 34, recess lill and transverse passages 6i, Si to the rear ends of the bores of the reciprocable cylinders 25, pressure fluid at the same time flowing through passages 66 inthe piston rods 22 to the forward ends of the bores of the stationary cylinders 20, 25. Simultaneously, the rear ends of the bores of the feed cylinders 2i), 20 and the forward ends of the bores of the feed cylinders 25, 25 are connected to exhaust through passages 3l in the piston rods, passages 51, groove 56, passage 55 in the connecting rod 34, groove 54, the passage 52a, groove 52 on the control valve 4l and exhaust passage 63. The pressure fluid flowing to the rear ends of thebores of the feed cylinders 25 acts on the rear end walls of the cylinder bores to move the cylinders 25 rearwardly with respect to the pistons 2l, vwhile the pressure fluid flowing to the forward ends of the bores of the cylinders 28 acts on the forward pressure areas of-the pistons 2| to move the latter rearwardly with respect to their cylinders, moving therewith the cylinders 25, when the latter reach their extreme limit of rearward movement with respect to the pistons 2l', and as a result, the rock drill I is moved rearwardly along the guiding surfaces of the tubular guide members. The pressure fluid acting on the rear end walls of the bores of the cylinders 25 is admitted substantially directly thereto while the pressure flowing to the forward ends of the bores of the cylinders 2li must pass through the passages 55 in the piston rods. Accordingly, the cylinders 25 may move more rapidly relative to the pistons 2l than do the pistons 2l relative to the cylinders 20, particularly during relative free retractive movement, and during retraction, as well as during forward feed, simultaneous relative movement between the elements of each cylinder and piston couple probably occurs to a large extent. It will be evident that the forward feeding pressure may be regulated by the reducing valve 45, and the feeding pressure may be controlled at will and the feed reversed by the control valve 45, all in the manner described in the patent above referred to.

In the modified form of the invention shown in Figs. 10 to 14, inclusive, the rock drill and the specific structure of the feeding means are similar to those disclosed in the form of the invention above described. In this instance, however, the rock drill has formed on the cylinder of its hammer motor lateral guides 1i, H slidably mounted in longitudinal guideways l2, 12 formed on the upper forward portion of but a single tubular guide member 13. The forward portion of the tubular guide member 13 has formed therein a feed cylinder T4, while the rearward portion of the tubular guide member has reciprocably mounted in its bore 15 a feed cylinder 15. The rear head 'H of the rock drill has an integral rearward extension i8 connected at 'i9 to the rearward end of the reciprocable feed cylinder '56, this connection extending through a longitudinal slot formed in the upper surface of the tubular guide member. As the specific feed cylinder and piston structure and the passage means for supplying pressure fluid to the feed cylinders and the control valves therefor are identical to those described above in the form of the invention disclosed in Figs. 1 to 9, inclusive, the main difference in this form of the invention being that but a single guide member together with a single cylinder and piston couple, is employed, further description thereof is submitted to be unnecessary.

In the modified form of the invention shown in Figs. 15 to 19, inclusive, the rock drill and tubular guide member are similar to those disclosed in Fig. 10 of the form of the invention above described. In this instance, however, there is shown but a single elongated feed cylinder 8i guided within a bore 82 of a guide member 83, the guiding bore extending substantially throughout the length of the guide member. This feed cylinder is of a length substantially equal to the combined lengths of the cylinders'hl and 15 and contains in its bore 84 a stationary feed piston 85. This feed piston has a piston rod 86 extending forwardly through the packed front head 81 of the feed cylinder and secured at its forward end at 88 to the forward end wall 89 of the tubular guide member 83. The rock drill is connected by the connecting frame 'i8 with the rear end of the feed cylinder 8|, and the forward and reverse feed passages communicate respectively with a passage et communicating with the cylinder bore at the forward side of the feed piston 85 and a passage SI communicating with the rear end of the cylinder bore at the rear side of the feed piston. The guide member is formed with a longitudinal slot 92 through which the drillconnection extends into connection with the rear end of the feed cylinder, this slot permitting movement of the connecting frame with respect to the guide member during reciprocation of .the feed cylinder. The means for supplying pressure uid to the passages 953 and Si and the control valves therefor are the same as those above described.

The mode of operation of the modified form of the invention shown in Figs. 10l to 14, inclusive, is substantially the same as that described above in connection with the form of the invention shown in Figs. 1 to 9, inclusive. When pressure fluid is supplied through the supply passages to the forward end of the bore of the cylinder l and to the rear end of the bore of the stationary cylinder T4, the cylinder 'i6 is slid forwardly within the guiding bore 'i5 of the guide member, and as a result, the rock drill i is moved forwardly along its guideways l2, 'i2 relative to the guide member. When the position of the control valve d! is reversed, pressure fluid is supplied to the rear end of the bore of the cylinder 'i6 and to the forward end of the bore of the cylinder T4, and as a result, the rock drill is fed rearwardly along its guideways.

In the form of the invention shown in Figs. l5 to 19, inclusive, when pressure uid is supplied to the forward end `bore of the cylinder 8|, the latter is moved forwardly within the guiding bore 82 of the guide member 83 relative to the stationary feed piston B5, and as a result, the rock'drill l is fed forwardly along its guideways relative to the guide member 83. When pressure fluid is supplied to the rear end of the bore of the feed cylinder 8l, the latter is moved rearwardly in the guiding bore 82 of the guide member 83 with respect to the stationary feed piston 85, thereby moving the rock drill rearwardly along its guideways. As in the form of the invention described above, the forward feeding pressure may be regulated by the pressure reducing valve i6 and the feeding pressure may be controlledand the direction of feed reversed at will independently of the control valve 4l, by means of the control valve 45.

As a res-ult of this invention, it Will be noted that an improved rock drilling mechanism is provided having a novel feeding and guiding structure for the rock drill whereby the rock drill may be fed relative to the guiding means in an improved manner. It will further Vbe noted that Yby the provision of the extremely compact arrangement of the feeding and guiding elements, it is possible by an extremely compact structure, to

Vobtain a relatively long range of drill feed. It

will still further be noted that by the particular arrangement shown, it is possible to guide the rock drill directly on the tubular guiding means and to effect feed of the rock drill directly bythe reciprocable feed cylinder which is guided in the guiding means; it `being possible vby the particular arrangement shown to guide the rock drill on the forward portion of the guiding means and to feed the rock drill through a connection between the rear end of the reciprocable feed cylinder and the rear end of the rock drill. Other uses and advantages of the improved rock drilling mechanismwill be clearly apparent to those skilled in the art.

While there are in this application Specifically described several formsrwhich the invention may assume in practice, it will be understood that these forms of the same are shown for purposes of illustration and that the invention may be further modified and embodied in various other forms without departing from its spirit or the scope of the appendedclaims.

What I claim as new and desire to secure by Letters Patent is:

l. In a rock drilling mechanism, guiding means comprising a tubular guide member having a longitudinal drill guiding surface and a guiding bore, `a rock drill guided on said guiding surface for movement longitudinally therealong, and feeding means for feeding the rock drill along said Vguiding surface comprising a feed cylinder reciprocable in said guiding bore of said guide member and Vcontaining a feed piston, and an elongated rigid connection extending longitudinally of said guide member between the rear end of said feed cylinder and the rear end of the rock drill for connecting the latter to the feed cylinder for movement therewith relative to said guide member. Y

2. In a rock drilling mechanism, guiding means comprising a tubular guide YmemberV having a longitudinal drill guiding Surface and a guiding bore, a rock drill guided on said guiding'surface for movement longitudinally therealong, and feeding means for feeding the rock drill along said guiding surface comprising va feed cylinder reciprocable in said guiding bore of said guide member and containing a feed piston, and an elongated rigid connectionextending longitudinally of said guide member between the rear end of said cylinder and the rear end of the rock drill for connecting the latter to the feed cylinder for movement therewith relative to said guide member, said guide member having a longitudinal slot through Vwhich said connection between the feed cylinder and the rock drill passes, said slot permitting longitudinal move ment of said connection relative to the `guide member during reciprocation of the feed cylinder in said guiding bore.

3. In a rock drilling mechanism, guiding means comprising a tubular guide member having a longitudinal drill guiding surface and a guiding bore, a rock drill guided on said guiding surface for movement longitudinally therealong, and feeding means for moving said rock drill along said guiding surface Vcomprising .a feed cylinder reciprocable in said guiding bore in said guide member and having a boreY containing a feed piston, an elongated rigid connection extending longitudinally of said guide member between the rear end of said feed cylinder and the rear end of the rock drill for connecting the latter to the feed cylinder for movement therewith relative to said guide'memben and means including passage means in said connection for supplying pressure uid to the bore of said feed cylinder to effect reciprocation of the latter.

4. In a rock, drilling mechanism, guiding means comprising a tubular guide member having a longitudinal guide way and a guiding bore, a

rock drill guided on said guideway, and means for feeding the rock drill along said guideway comprising, a stationary feed cylinder within said guide member, a reciprocable feed cylinder coaxial with said stationary feed cylinder and guided in said guiding bore, by the walls of the latter, independently of the drill guideway, said drill being guided by its guideway independently of said reciprocable cylinder, feed pistons contained in said cylinders respectively, a common piston rod connecting said pistons together, and a connection between said reciprocable cylinder and the rock drill.

5. In a rock drilling mechanism, guiding means comprising a guide member, a rock drill guided on said guide member, and means for feeding the rock drill along said guide member comprising a stationary feed cylinder, a reciprocable feed cylinder coaxial with said feed cylinder and guided by said 'guide member, pistons contained in said feed cylinders respectively, a common piston rod connecting said pistons together, an elongated rigid connection extending longitudinally between the rear endrof said reciprocable feed cylinder andthe rear end of the rock drill, and means for supplying pressure fluid to said cylinders to effectl reciprocation of the piston contained insaid stationary cylinder relative to the latter and reciprocation of said reciprocable cylinder relative to its piston.

6. In a rock drilling mechanism, guiding means comprising a yguide member, a rock drill guided on said guide member, and means for feedingY the rock drill along said guide member comprising a stationary feed cylinder within the forward portion of said guide member, a reciprocable feed cylinder coaxial with said feed cylinder and guided within the rearward portionof said guide member, pistons contained in said feed cylinders respectively, a common piston rod connecting said pistons together, a connection between the rear end of said reciprocable feed cylinder and the rear end of the rock drill, and means for supplying pressure fluid to said cylinders to effect reciprocation of the piston contained in the stationary cylinder relative to the latter and reciprocation of said reciprocable cylinder relative to its piston.

'7. In a rock drilling mechanism, guiding means comprising a guide member having longitudinal v guideways extending longitudinally along different portions thereof, a rock drill guided on one of said guideways, and means for feeding the rock drill along its lguideway comprising a stationary feed cylinder on the guide member, a reciprocable feed cylinder coaxial with said stationary cylinder and guided on the other of said guideways independently of the guideway on which the drill is guided, said drill being guided by its guideway independently of said reciprocable cylinder, feed pistons contained in said cylinders respectively, a common piston rod connecting said feed pistons together, a connection between said reciprocable cylinder and the rock drill, and means for supplying pressure fluid to said cylinders to effect reciprocation of the piston contained in the stationary cylinder relative to the latter and reciprocation of said reciprocable cylinder relative to its piston.

8. In a rock drilling mechanism, guiding means comprising a guide member, a rock drill guided on the forward portion of said guide member, and means for feeding the rock drill along said guide member comprising a stationary feed cylinder within the forward portion of said guide member, a reciprocable feed cylinder coaxial with said stationary cylinder and guided within the rearward portion of said guide member, pistons contained in said cylinders respectively, a common piston rod connecting said pistons together, and a connection between the rear end of said reciprocable cylinder and the rear end of the rock drill.

9. In a rock drilling mechanism, guiding means comprising a guide cylinder, a rock drill guided on said guide cylinder, and means for feeding the rock drill along said guide cylinder comprising a stationary feed cylinder within the forward portion of said guide cylinder, a reciprocable feed cylinder coaxial with said stationary cylinder and vguided within the rearward portion of said guide cylinder, pistons contained in said cylinders respectively and connected together forv movement in unison, and a connection between the rear end of said reciprocable cylinder and the rear end of the'rock drill, said guide cylinder having a longitudinal slot opening through the wall thereof and through which said connection passes, said slot permitting longitudinal movement of said connection relative to said guide cylinder. v

10. In a rock drilling mechanism, guiding means comprising a pair-of parallel guide members, a rock drill guided on said guide members, and feeding means Vfor feeding said rock drill along said guide members 'including reciprocable feed cylinders guided on said guide members respectively, and an elongated arm-like connection extending longitudinally of said guide members therebetween and between said cylinders for connecting the rock drill to said recprocable cylinders for movement therewith relative to said guide members.

11. In a rock drilling mechanism, guiding means comprising a pair of parallel. guide members, a rock drill guided on said guide members, and feeding means for feeding said rock drill along said guide members including stationary feed cylinders on the guide members, reciprocable feed cylinders coaxial with said stationary cylinders respectively and guided by said guide members, pistons contained in said stationary cylinders, pistons contained in said reciprocable cylinders, piston rods connecting the pistons in said reciprocable cylinders to the pistons in said stationary cylinders, and a connection between said reciprocable cylinders and the rock drill.

12. In a rock drilling mechanism, guiding means comprising a pair of parallel guide members, a. rock drill guided on said guide members, and feeding means for feeding said rock drill along said guide members including stationary feed cylinders Within the forward portions of said guide members, reciprocable feed cylinders coaxial with said stationary feed cylinders respectively and guided by the rearward portions of said guide members, pistons contained in said stationary cylinders, pistons contained in said reciprocable cylinders, piston rods connecting said pistons in said reciprocable cylinders to the pistons in said stationary cylinders, and a connection between the rear ends of said reciprocable cylinders and the rear end of the rock drill.

13. In a rock drilling mechanism, guiding means comprising a guide cylinder having a bore and an end wall, a rock drill guided on said .guide cylinder, and means for feeding the rock drill relative to said guide cylinder including a feed cylinder reciprocably mounted in the bore of said guide cylinder, a feed piston contained in piston and to the end wall of said guide cylinder for holding said piston stationary, and an elongated rigid connection extending longitudinally of said guide cylinder between said reciprocable cylinder and the rock drill for connecting the latter to said feed cylinder for movement therewith relative to said guide cylinder.

14. In a rock drilling mechanism, guiding means comprising a guide cylinder having a bore and a front end Wall, a rock drill guided lon the forward portion of said guide cylinder, and means for feeding the rock drill relative to said guide cylinder including a feed cylinder reciprocably mounted in the bore of said guide cylinder, a feed piston contained in said feed cylinder, a piston rod connected to said piston and to said front end wall of said guide cylinder for holding said piston stationary, and an elongated rigid connection extending longitudinally of said guide cylinder between the rear end. of said reciprocable feed cylinder and the rear end of the rock drill for connecting the latter to said feed cylinder for movement therewith relative to said guide cylinder. v

15. In a Vrock drilling mechanism, guiding means comprising a guide member having a longitudinal drill guideway, a rock drilll slidably guided on said drill guideway, andfmeans Vfor feeding the rock drill along said guideway comprising a stationary feed cylinder on the forward portion of said guide member, a reciprocable feed cylinder coaxial with saidv stationary feed cylinder andv guided on the rearward portion of said guide member, pistons contained in said coaxial cylinders respectively, a common piston rod connecting said pistons together, and a connection between the reciprocable feedl cylinder and the rock drill.

16. In a rock drillingV mechanism, guidingV means comprising a guide cylinder having a bore and an end wall, a rock drill guided on said guide cylinder wholly externally thereof, and means for feeding the rock drill relative to said guide cylinder including a feed cylinder reciprocably mounted in the bore of said guide cylinder and guided wholly internally within the guide cylinder, a feed piston contained inY said feed cylinder, a piston rod connected to said piston and to the end wall of said lguide cylinder for hold-V ing said piston stationary, and a connection besaid feed cylinder, a piston rod connected to said tween said reciprocable feed cylinder and the rock drill.

17. In a rock Vdrilling mechanism, guiding means comprising a cylindrical guide member having a guideway and a bore, a rock drill guided on said guideway wholly externally of said guide member, and means for feeding the rock drill along said guideway including alined, cylinder and piston feeding motors having their cylinders arranged internally within said guide member and acting accumulatively to eifect drill feed.

18. In a rock drilling mechanism, guiding means comprising aV guide member having a guideway, a rock drill guided on said guideway wholly externally of said guide member, and means for feeding the rock drill along said guideway includingalined, cylinder and piston feeding motors acting accumulatively to effect drill feed, one of said motors having its feed cylinder guided for reciprocation on said guide member and the cylinders of both motors arranged internally within said guide member, and a connection between said reciprocable feed cylinder and the rock drill. Y

19. In a rock drilling, mechanism, guiding means ccmprisinga pair of parallel guide members, a rock drill guided on said guide members Wholly externally of the latter, and feeding Vmeans for feeding the rock drill along said guide members including reciprocable feed cylinders guided on said guide members respectively wholly internally within the latter, and a connection between said cylinders and the rock drill.

20. In a rock drilling mechanism, guiding means comprising a pairA of Vtubular guide members Varranged in parallel side by side relation, a rock drill guided directly on the exterior surfaces ofsaid guide members therebetween, and feeding meansfor feeding the rock drill along said guide members including stationary feed cylinders, alined reciprocable feed cylinders, said stationary cylinders mounted within said guide members and said reciprocable feed cylinders Yguided within said guide members, pistons contained in said cylinders respectively, piston rods connecting the pistons in the stationary cylinders with the pistons Yin the reciprocable cylinders, and a rigid connection between said reciprocable cylinders and the rock drill.

CHARLES F. OSGOOD. 

